Method of and apparatus for treating metal



H. 0. swm. I w METHOD or AND APPARATUS FOR IREATINGQM'ET'WZI APPLICATIONFILED MAR. 21, 1920.

v UNITED STATES PATENT OFFICE.

HERBERT D. SWIFT, OF NEWYORK, N. Y., ASSIGNOB TO INTERNATIONAL AUTOMATICAPPLIANCE CORPORATION, A CORPORATION OF NEW YORK.

ma'rnon or AND arrmrus ro'n 'rima'rme METAL To all whom it may concern:

Be it known that I, HERBERT D. SWIFT, a citizen of the United States,and a resident of the borough of Manhattan, city, county,

' and State of New York, have invented certain new and usefulImprovements in Methods of and Apparatus for Treating Metal, of whichthe following is a specification.

This invention relates to the annealing of metals and is particularlyadapted for annealing metals as they come from the rolling mills,irrespective of the particular shape of the metal, that is to say,whether in the form of a bar, strip or wire. It is to be understood,therefore, that in its broadest aspects the present invention isdirected to a method of and apparatus for use in connection with anymetal to be annealed.

It has been common practice prior to this invention to make up a numberof coils of metal after coming from the rolling mills and to take thesemetal coils and place them, one ontop of the other, in an annealing ovenfor a predetermined length of time, depend ing upon the degree of temperdesired. These metal coils are then taken from the annealing oven andcleaned, sometimes necessitatinguncoiling of the metal, cleaning it, andthen coiling it up again. This method is unsatisfactory for obviousreasons, inasmuch as a cat deal of time is consumed in the coi in oeration which time is greatly increase 0 course, in the event of themetal being cleaned in the manner referred to, and it is not alwayspossible to succeed in annealing the metal uniformly throughout, that isto say, not only may each coil be improperly annealed but there ma be alack of uniformity comparing one coil with another.

In annealing bar metal it is common practice to place thesame in anannealing oven where it is subiected to a predetermined temperature untithe metal is annealed sufficiently.

All 'of these methods are unsatisfactory, however, as a great deal oftime is necessarily consumed in the annealing operation and furthermoreit'seems to be practically impossible to get a uniformly annealedproduct.

It is an object of the present invention,

Specification of Letters Patent. I Patented Aug, 9, 1921,

Application filed March 27, 1920. Serial No. 389,361.

' therefore, to provide a method of and apparatus for annealing metalswherein these defects are overcome.

A further object of the invention is to provide a method of andapparatus for andirectly into the annealing chamber, and

after being annealed and not until then, coiled up. If desired andshould it be necessary to clean the metal after annealing, this may bedone as the metal comes from the annealing chamber, so that there willbe the continuous process of rolling the metal, annealing, cleaning ifnecesary, and finally coiling in a finished condition.

A further object of the invention is the provision of means whereby themetal while being annealed may be'passed through a set of reducing rollsthereby effecting a saving in rolling or drawing costs.

Other and further objects will be apparent from the detailed descrlptionto follow.

In its broadest aspects the present invention comprises a method andapparatus whereby an electric current, either impressed or induced, and.of sufficient amperage, is

passed through a closed circuit, part of which is composed of the metalto be annealed, for a sufficient length of time to generate an annealingheat in said metal.

In the accompanying drawing I have illustrated in perspective anembodiment of my invention wherein a plurality of metal sections may beannealed simultaneously.

Referring to the drawing in detail, 54 designates the metal shell of atransformer, the V end of these bars. Immediately above the bars arerollers 61. The metal 62 to be annealed may be fed between the contactbars 60 and the rollers 61 and if the primary 55 of the transformer beenergized by current from the generator 65, current will. be 1nduced inthe metal sections 62 which will be short-circuited through the contactbars 58 and the metal sections.

In order that the, annealing temperature may be varied I have providedresistance coil 64 adapted to be cut in and out or varied by the arm 65.

The rollers 60 and 61 are preferably, though not necessarily, providedwith peripheral grooves 66 to grip the metal sections as the same arefed through the apparatus. t will be obvious that if desired the rollers61 may be sprlng ressed-.

At times it may be desirab e to reduce the metal during the annealingoperation and to this end I have provided reducing rollers 67 and 68mounted on suitable supports 69. It will be understood from the drawingsthat a set of reducing rollers for each metal section may be provided.These rollers are positioned intermediate the contact bars 58 so thatthe metal sections will be annealed and reduced simultaneously which isof distinct advantage in that otherwise after reduction the metalsections would necessarily have to go throu h theannealing operationagain.

From t e foregoing it will be seen, that I have provided a method of andapparatus for annealing metal sections wherein the metal to be annealedis heated by short-circuiting an electric current either induced orimpressed through the same whereby one or more metal sections may beannealed simultaneously. It will be obvious also that I have provided amethod and a paratus whereby the metal may be reduce during theannealing operation. Furthermore I have provided means whereby theannealing temperature may be varied as desired.

While .I have illustrated an embodiment of my invention, it is to beunderstood that changes may be made in the details of constructionillustrated within the purview of the'in vention.v

In this illustration two strips or sections of metal have beenillustrated which will be annealed simultaneously but it is to beunderstood that more than two strips or sections may be annealedsimultaneously 'if desired.

What is claimed as new is:

1. The method of annealing metal which method consists in inducing inthe metal to be annealed an electric current of sufiicient amperage andmaintained for a suflicient length of time to generate an annealing heatin said metal.

2. The method of annealing metal which method consists in inducing in aplurality of metal sections simultaneously electric cur annealed togenerate an annealing heat in said metal, and at the same time passingthe metal through reducing rolls.

4. In an apparatus of the class described, the combination of a primarywinding, contact bars for the reception of metal sections to beannealed, and means for energizing said primary winding whereby inducedcurrent will be short-circuited through the metal sections to anneal thesame.

5. In an apparatus of the class described, the combination of a primarywinding, a contact bar on opposite sides of said primary winding, and apair of rollers supported at each end of said contact bars whereby whenthe primary winding is energized an induced current will beshort-circuited through metal sections bridging said contact bars andbetween said rollers.

6. In an apparatus of the class described, the combination of a primarywinding, a contact bar on opposite sides of said winding, and reducingmeans intermediate said contact bars, whereby when said primary windingis energized an induced current will be short-circuited throu h metalsections bridging said contact ars and passing through the reducingmeans.

7. In an apparatus of the class described, the combination of means forannealing metal sections and means for rolling the sections during theannealing operation.

8. In an apparatus of the class described, the combination of means forshort-circuiting-an electric current through a section of metal toanneal the same and means for simultaneously reducing the cross-sectionof said metal.

9. In combination a transformer frame, a primary winding interme iatethe ends of said frame, means for energizing said winding, a contact baron each side of said winding intermediate it and the end of said frame,and metal sections bridging said contact bars.

10. In combination, atransformer frame, a primary winding supportedthereby, contact bars between said winding and the ends primar windingis excited a current will be induce in the metal sections andshort-circuited thereby.

11. In an apparatus of the class described, the combination of a primarywinding, contact bars for the reception of metal sections to beannealed, means for energizing said primary winding whereb inducedcurrent will be short-circuited through the metal sections to anneal thesame, and means for rolling the metal sections during the annealingoperation.

12; The method of treating metals which method consists insimultaneously annealingjand reducing the metal.

his specification signed this 25th day of March, 1920.

HERBERT D. SWIFT.

